What are the disadvantages of the progestin only pill?

Women may not have regular periods while they are taking progestin-only pills. Periods may become irregular, light, or more frequent or may stop altogether. This usually improves within the first 6 months of use, and is not harmful, but some women may find it annoying. Changing to a different brand of pill may help but there is not data on this.

The progestin-only pill does not protect against sexually transmitted infections, so women may need to use condoms as well.